How to use findmax!?

Raymond · July 4, 2022, 7:41am

Dear all,

Can you give me an example of how to use findmax!?

lawless-m · July 4, 2022, 7:59am

I don’t know much about it myself but you can look at the unit tests

JuliaLang/julia/blob/742b9abb4dd4621b667ec5bb3434b8b3602f96fd/test/reducedim.jl#L213-L221


      
          for (tup, rval, rind) in [((1,), [5.0 5.0 6.0], [CartesianIndex(2,1) CartesianIndex(1,2) CartesianIndex(1,3)]),
                                    ((2,), reshape([6.0,5.0], 2, 1), reshape([CartesianIndex(1,3),CartesianIndex(2,1)], 2, 1)),
                                    ((1,2), fill(6.0,1,1),fill(CartesianIndex(1,3),1,1))]
              @test findmax(A, dims=tup) == (rval, rind)
              @test findmax!(similar(rval), similar(rind), A) == (rval, rind)
              @test isequal(maximum(A, dims=tup), rval)
              @test isequal(maximum!(similar(rval), A), rval)
              @test isequal(maximum!(copy(rval), A, init=false), rval)
          end

jishnub · July 4, 2022, 8:47am

julia> rval = zeros(); rind = zeros(Int);

julia> findmax!(rval, rind, [1:5; 4:-1:1])
(fill(5.0), fill(5))

julia> rval
0-dimensional Array{Float64, 0}:
5.0

julia> rind
0-dimensional Array{Int64, 0}:
5

Raymond · July 4, 2022, 9:03am

Thanks, This is helpful to me.